1. Field of the Invention
The present invention is an electronic boiling sensor attachable to a pot above the water which audibly or visually indicates that the water in the pot is boiling.
2. Background of the Prior Art
There are a number of ways of sensing boiling other than merely making continuous checks on the condition of water in a pot being heated. It is desirable to known when liquid is boiling because many cooking procedures being when the water being used begins to boil. When water is first placed in a pot and heated for boiling, it is difficult to gauge accurately when boiling will start because the amount of water, its initial temperature, the conductivity of the pot and the heat quantity to the pot vary. Time is wasted continually checking on the liquid to see if boiling has begun, and continued heating beyond boiled without actual cooking wastes energy. On the other hand, some liquid should not be heated to boiling or should not boil too vigorously. Certain foods spill over, overcook or are burned by too vigorous heating.
There are a number of previous devices for testing whether water is boiling. One common way is to pass the collected steam through a whistle. This is a common means in tea kettles. A whistle incorporated in a pot or pan cover is disclosed in Emslie, U.S. Pat. No. 957,633 (1910). One may not want to use a cover, however, and such a system would require a separate cover with a whistle for each different sized pot.
Boiling can also be sensed by a temperature probe. It is not desirable to place the probe in the liquid itself because the device will have to be cleaned. Simple thermometers must be read, and reading a thermometer offers no advantage over merely checking the liquid visually to see if it is boiling. Electric temperature sensors that would yield audible or visual signal when a certain liquid temperature is reached might be perceived as potential sources of contamination of the liquid and still require cleaning. Moreover the boiling temperature varies greatly. Temperature sensing of the vapor is also inaccurate because the vapor temperature also fluctuates. One frequently finds that the temperature of the vapor decreases after the liquid starts boiling.